In recent years considerable attention has been given by designers and manufacturers of medical equipment to providing medical practitioners with improved medical devices for withdrawing patient body fluids or for injecting liquid medications or other fluids into a patient's body. Such devices typically utilize a double-ended needle in combination with an evacuated tube collector, a hypodermic syringe, supply tube, or the like. In many instances the needled devices have included some form of protective shield that surrounds the needle component to minimize the risk of accidental needlestick injury to the using practitioner due to inadvertent careless device handling. Also, the problem of providing adequate protection against inadvertent injury has received increased attention in recent years because of the prevalence of certain communicable diseases such as acquired immuno-deficiency syndrome which are known to be transmitted by contact with host human body fluids.
U.S. Pat. No. 4,752,290 issued to Schramm, for instance, discloses a needle shield having a series of raked teeth that is adapted to lock the shield around the needle in a substantially non-releasable position. Similarly, U.S. Pat. No. 4,782,841 issued in the name of Lopez teaches a needle guard member which, upon movement to a second position, is permanently locked in place by an included locking element.
U.S. Pat. No. 4,804,371 issued in the name of Vaillancourt discloses a needle sheath which is urged into its protective position around a needle point by action of a previously compressed compression spring.
U.S. Pat. No. 4,894,055 granted to Sudnak also teaches use of a spring-urged needle guard assembly as does U.S. Pat. No. 4,900,311 issued in the name of Stern et al. In the case of the latter patent the needle guard has an elliptical cross-sectional configuration and is made of a resilient material. Upon lateral compression the needle guard may be moved longitudinally between its two operative positions.
Still another patent teaching the use of a compression spring to effect movement of a protective needle housing is U.S. Pat. No. 4,929,237 issued in the name of Medway.
U.S. Pat. No. 4,947,863 granted to Haber et al. discloses a safety blood collection tube holder in which the device is provided with a plurality of successive energy absorbing and force dissipating stations at an inner cylinder. Such stations function to transform jarring impact locking forces into relatively smooth deceleration forces so as to avoid whiplash of the needle and possible splattering of that portion of the blood sample contained in the needle end.
U.S. Pat. No. 4,941,730 issued in the name of Poncy teaches a hypodermic syringe protective cap that must be rotated between first and second positions to enable the cap to be moved from an extended protective position to a retracted position exposing the syringe needle.
U.S. Pat. No. 5,030,209 granted to Wanderer et al. teaches a holder for a double-ended blood collection retractable needle with a needle retraction feature that may be readily actuated or manipulated using only one of the user's hands.
Also, U.S. Pat. 5,067,490 granted to Haber teaches a blood collection device having a double-ended needle and a protective outer sleeve. The Haber needle carrier is automatically locked into its needle-protected condition upon retraction of the outer sleeve element.
Other U.S. Patents granted by the U.S. Patent and Trademark Office and disclosing details of construction of additional medical needle devices having various guard or shield design features for protecting using medical practitioners against an accidental "needlestick" and possible consequential infection include: U.S. Pat. No. 5,067,945 issued in the name of Ryan et al., U.S. Pat. No. 5,070,884 issued in the name of Columbus et al., U.S. Pat. No. 5,070,885 issued in the name of Bonaldo, U.S. Pat. No. 5,086,780 issued in the name of Schmitt, and U.S. Reissue Pat. No. 33,585 issued in the name of Haber et al.
None of the above summarized or listed disclosures, however, provides a medical needle and needle sheath assembly which, upon extension of the included sheath or shield element, accomplishes the functions of automatically wiping the exterior of the wetted protruding needle with an absorbent material and afterwards placing a barrier in blocking alignment with the shielded needle to prevent a subsequent retraction of the in-place, extended sheath. The implementation of such functions will prevent subsequent exposure of the previously-used needle tip and possible needlestick injury to the using practitioner.